This invention pertains to manned submarines.
The growing importance of offshore activities, especially those connected with the exploration for and recovery of crude oil and gas, has increased the need for reliable underwater craft for housing men and equipment involved in underwater activities. Proposals have heretofore been made involving manned submarines. Exemplary of such proposals are the disclosures of U.S. patent No. 1,814,689 issued to Fieshaber on July 14, 1931; U.S. Pat. No. 3,292,564 issued to Lehman on Dec. 20, 1966; U.S. Pat. No. 3,613,615 issued to Sturm et al on Oct. 19, 1971; U.S. Pat. No. 3,688,720 issued to Lok on Sept. 5, 1972; and U.S. Pat. No. 3,713,411 issued to Bordessoule on Jan. 30, 1973.
Many commercial offshore activities require the attention of underwater personnel for numerous man-hours. At present these activities rely on a surface vessel or platform for support and hence are subject in varying degree to surface weather conditions. As an example, heavy construction in the North Sea at present is only possible for one or two days out of ten during the worst six months of the year, and most activities aside from those involving semi-submersible drilling rigs, simply stop during this period. Another factor is that overall efficiency in performance is somewhat lessened when personnel are repeatedly transported between the submerged work site and living quarters above the water surface. A large, autonomous heavily-powered underwater construction submarine would be an efficient and cost-effective way of avoiding these kinds of problems.
However, the long-term lift support requirement of diving personnel who are subjected to repeated and prolonged exposure to alien conditions, presents considerable physical problems and renders it difficult for divers to live in submarines.
In addition, the present day utilization of submarines for performing heavy-duty underwater activities leaves much room for improvement, especially in areas such as the transporting of large heavy equipment like pipe alignment frames and welding habitats, the ability to make heavy lifts with adequate control, and the supply of power and heavy duty tools for divers. Many submarines are not able to effectively and safely perform functions such as these, necessitating the expense and efforts of additional machines and man power.
Another problem connected with underwater activities involves the requirement of divers to perform repairs or inspections in or around structures which are not accessible to the divers' life support equipment. In this connection, underwater activities in severe environments, such as deep frigid waters, requires the use of special diving suits which are supplied via umbilical conduits with breathing gas, communications, and a heating medium for the diver, and a diver's life-line. Such equipment can be carried within a diving bell that is suspended from a surface vessel, with umbilical conduits being about 75 to 100 feet in length. Frequently, however, underwater activities within structures like offshore drilling platforms cannot be effectively performed with such equipment. That is, a diving bell cannot be suspended within the open-trussed support jacket which carries the platform. Such jackets are often hundreds of feet across, so that even if a diving bell is positioned adjacent the jacket exterior, the normal extent of the umbilical conduits is not sufficient to provide an effective range of maneuverability for the divers.
It is, therefore, an object of the present invention to provide novel methods and apparatus for obviating or minimizing problems of the sort previously discussed.
It is another object of the invention to provide a novel manned submarine vessel.
It is a further object of the present invention to provide novel methods and apparatus for improving the underwater versatility of manned submarines.
It is another object of the invention to provide a novel submarine which effectively accommodates diver and non-diver personnel for prolonged periods of habitation.
It is a further object of the invention to provide a novel manned submarine vessel which is capable of lifting large, heavy loads in a controlled manner.
It is an additional object of the invention to provide novel methods and apparatus for enabling a manned submarine to carry out and observe underwater explosions.
It is a further object of the invention to provide novel methods and apparatus for increasing the safe maneuvering range of divers within structures of limited accessibility.